Papers by Keyword: Cantilever

Abstract: Based on the relation between the wavelength shift of sensing FBG and the strain, a flow measuring device of the circular target binding Fiber Bragg Grating with the cantilever is designed and the mathematical model based on a circular target flow measurement system is established. Through the flow experiment, we can get the flow test result. The experimental data error analysis can be concluded to verify the feasibility and precision of the design.

Abstract: This Paper presents the design and simulation of single walled carbon nanotube (SWCNT) based cantilever type electrostatic actuator using finite element analysis method (FEM). The pull-in voltage has been calculated for various chirality of the nanotube based cantilever beam actuators. The pull-in voltage are obtained for the various gap between electrode and ground of the cantilever beam through extensive simulations using ANSYS software. The results obtained shows that pull-in voltages varies from 2.5 to 13.5V with respect to nanotube chirality and gap length.

Abstract: Cantilever with modified aptamers on the gold surface was employed to detect platelet-derived growth factor-BB (PDGF-BB) and cocaine. The deflection increased when PDGF-BB and cocaine were added into the flowing cell, respectively. The defection depended on the concentration of PDGF-BB and cocaine. It was also found the microcantiver went back to the same position as without cocaine after adding cocaine aptamer in situ, which proved that the cantilever could be reused. The deflection arose from the specific interaction between aptamer and its target.

Abstract: A mathematical model for the Double-crystal Piezoelectric Cantilever Generating Unit (DPCGU) was built and a new Piezoelectric Generator Based on Stairs (PGBS) with DPCGU was designed in this paper, the energy conversion efficiency of the PGBS which makes use of human kinetic energy was improved and the deficiencies of existing piezoelectric energy harvesting technology were avoided. The experiment of the generating capacity for the PGBS was carried out, and the consistency of the mathematical model results and the experimental results was verified by comparison.

Abstract: This paper deals with designing a MEMS cantilever which can function as biosensor for tuberculosis detection. In this study we investigate the MEMS based biosensor to detect Tuberculosis based on capacitive sensing, peizoresistive and resonant frequency methods. We also examine which method has enhanced performance. Early detection and treatment of diseases can facilitated only if we are able to detect pathogenic and physiologically relevant molecules in the body with high sensitivity and specificity.Early detection of diseases reduce the risk of patients being pushed to advanced stages of many diseases.This sensor is used for early detection of Tuberculosis using the antigen antibody reaction.Tuberculosis can be detected by monitoring the presence of disease causing antigen in the blood stream.The presence of disease causing antigen in the blood can be monitered by using this microcantilever based diagnostic device. The sensing principle varies according to the device, the nature of the analyte molecules, and the precision required. Capacitance, piezoresistance and resonance frequency are among the read out methods depending upon the mechanical properties of the device. The biosensor structure is designed and simulated using Coventorware, Intellisuit and HFSS software. This microcantilever based biosensor can detect tuberculosis by immobilizing specific antibodies on the microcantilever.These antibodies are specific to TB antigen 85 complex.When the patient sample containing TB antigen 85 complex is placed on the cantilever biomolecular interactions take place between TB antigens and the antibodies immobilized on the upper surface of the microcantilever.This causes microcantilever to bend and facilitates to detect the presence of Tuberculosis.Bending of the cantilever can be measured by capacitive sensing, peizoresistive and resonant frequency shift methods.

Abstract: To meet a high-precision accelerometer resistance of temperature, humidity and other external noise, a new multi-ring cascade optical accelerometer structure is designed. The micro-ring resonator on the cantilever beam based on the photo-elastic effect and the contrast are fabricated with the same manufacturing process and size, which can effectively meet the consistency of the contrast and test micro-ring resonator on the cantilever. The one resonance point curve will split into two under the acceleration, thus the acceleration value can be obtained by detecting the wavelength of the two resonant points. By testing the cascade race-track shaped micro-ring resonator at different temperatures, the Q=10⁴, the test requirement of cascade race-track shaped micro-ring accelerometer in different environments is greatly met. The design can be widely applied to the occasions of penetration system with high impact, strong vibration and so on. And the anti-noise and anti-jamming features of the integrated miniaturized high-sensitivity MOEMS sensors are realized.

Abstract: According to the mechanics analysis of the flexible cantilever beam in the uniform load distribution, the corresponding mathematical model is established. Applying quasi-linear analysis and perturbation solution in order to convert to complex integral and differential formula into its power series form, then derives the general formula of dimensionless deflection formula. Last we further discussed the deflection formula and analysis the force situation of the beam.

Abstract: In this paper, micro-Raman characterizations and Finite element modeling (FEM) of microstructures (cantilever, bridge, planar rotating probe) realized on single-crystal (100) 3C-SiC/Si films are performed. Transverse optical (TO) Raman mode analysis reveals the stress relaxation on the free standing structure (796.5 cm-1) respect to the stressed unreleased region (795.7 cm-1). The TO Raman mode exhibits an intense shift, up to 2 cm-1, located on the undercut region, where the Silicon substrate starts to be released. Such effect is ascribed to the modification of the Raman stress tensor that makes the generalized axial regime, described by diagonal components of the Raman stress tensor, unsuitable to describe the stress status on this region. Raman maps analysis and FEM simulations show the “activation” of the shear stress, i.e. non-diagonal components of the stress tensor. The aim of future works will be to minimize the stress field generation and the defects density within the epitaxial layer.

Abstract: After the devastating floods in the Europe and Czech Republic especially, in 1997, 2002 and 2007 years, the need of the anti-flood protection was very actual and delicate. One of the ways, how to solve this problem in the case of usual or lower water level, is the usage of anti-flood barriers. The paper is focused on the experimental verification of the actual behaviour, load-carrying capacity and failure mechanisms of the cantilevers made of FRP composite profiles PREFEN, which are in reality used as columns of anti-flood barriers. The investigated water-proof profile of H-cross-section is composed of epoxy resin and glass fibres.

Abstract: A Fourier Transform method is applied to determine the displacements of a cantilever beam subjected to a multi-frequency excitations at the base. To dampen the displacements of the beam, a point mass is attached to the beam. The position of the mass on the beam is determined such that the overall deflections of the beam are minimal. It is shown that these attachments to the beam are effective in reducing the vibrations of the beam but their position is frequency dependent. It is shown that the low frequency component of the external excitation is most important in finding the optimal position of the mass.